MRI and the endolymphatic space

1 July 2016 | Sangeeta Maini, Bhaskar Ram | Delayed endolymphatic hydrops (DEH), bilateral case, endolymphatic hydrops (EH), gadolinium-enhanced inner ear MRI, semiquantitative analysis

This is an interesting study which was performed to evaluate the endolymphatic space in patients with endolymphatic hydrops (EH), using MR imaging. Seven patients aged between 21–77 years; five female, two male with unilateral or bilateral symptoms of EH were evaluated with gadolinium-enhanced inner ear MR imaging. All patients underwent 3T MR imaging four hours after intravenous injection of gadolinium. Software was used to determine the size of the endolymphatic space. Pure tone audiometry and caloric testing using an electronystagmogram were carried out. On analysis of the MR images one side of the endolymphatic space was dominantly extended in patients with ipsilateral EH, and both sides of the space were extended in patients with bilateral EH. In patients with ipsilateral EH, the volume ratio of endolymph to vestibule was 2.5 – 4.3 times that in the unaffected ear. The volume ratio of endolymph to vestibule was nearly equal in patients with bilateral EH. It would be a great help to otologists to have more objective evidence of EH as diagnosis is still based mainly on clinical presentation. A study with larger numbers is awaited!